铁道科学与工程学报2018，Vol.15Issue(3)：700-709,10.
T字形钢箱梁异形块设计及空间受力特性研究
Design and mechanical analysis of special T-shaped block of steel box girder
摘要
Abstract
The special T-shaped block of steel box girder is suitable for the design of large transport hub, but there are inevitable errors when analyzing its mechanical performance by general beam element because of its changeable live load distribution and obvious spatial effect. In order to understand its spatial mechanical performance comprehensively, the T-shaped block of steel box girder on 65#~68# pier in the mainline of Hongqi Road in Changsha was taken as engineering background. The general layout of box girder section, the thickness of top and bottom plate, and the size of transversal diaphragm plate and longitudinal ribbed stiffener were detailed discussed and finally determined. Based on the thick plate element considering shear deformation in MIDAS/Civil, the whole bridge spatial FEM model was precisely established. By studying structure displacement, cross section stress, end reaction, natural vibration characteristic and local buckling condition under different load cases, the rationality of bridge design scheme was verified. The results show there are obvious uneven phenomenon in structure displacement and end reaction; the displacement and end reaction in the same cross section still have lagre differences even under the dead load and this effect becomes more significant under the offset load. Under the most unfavorable combination of load case, the maximum Mises stress of steel box girder is 232.8 MPa, which occurs along the boundary between the plate and the stiffener of 66#b bearing; it is suggested that the components near the bearing should be suitably reinforced in structure design. Under the action of local wheel pressure, the transversal diaphragm has sufficient safety coefficient and the local buckling will not occur; it also indicates that the reinforced concrete bridge deck can multiply increase the stiffness of special-shaped steel bridge because it makes the load distribution more uniform. The results also can provide reference for design and calculation of similar bridges in the future.关键词
异形块/截面设计/空间效应/厚板单元/应力集中/局部屈曲Key words
special block/section design/spatial effect/thick plate element/stress concentration/local buckling分类
建筑与水利引用本文复制引用
刘建威,于鹏,李德建..T字形钢箱梁异形块设计及空间受力特性研究[J].铁道科学与工程学报,2018,15(3):700-709,10.基金项目
国家自然科学基金资助项目(51378504) （51378504）
